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Computer Science, Artificial Intelligence, Computer Vision, Special Effects, Image segmentation, and 15 moreDigital Watermarking, Wavelet, Stereoscopy, Object Recognition, Video Object, Lossy Compression, Computer Science and Information Technology, Video Tracking, Discrete wavelet transform, Trees (Mathematics), Watermark, High energy, Embedded Zerotree Wavelet, Ciencias Informáticas, and Video Signal Processing
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The concept of Metaverse and its applicability in the public sector as a tool to change the delivery of governmental services are discussed in this article. This study’s contribution is that it explores the opportunities and challenges of... more
The concept of Metaverse and its applicability in the public sector as a tool to change the delivery of governmental services are discussed in this article. This study’s contribution is that it explores the opportunities and challenges of the Metaverse’s adoption, so that decision-makers will be prepared before using the virtual world of the Metaverse to deliver public services. The quality of public services is a topic that many governments are attempting to address. Metaverse is a virtual environment that enhances the experience of obtaining government services by incorporating them into a virtual world. The purpose of this article is to explain how Metaverse works and why the public sector should use it. The benefits and drawbacks of Metaverse are discussed in detail in order to provide decision-makers with a clear picture of the technology’s worth.
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This paper focuses on the use of new technologies in educational practice. Despite the notion that students' familiarity with technological tools is essential for their learning development, the main question is still the following:... more
This paper focuses on the use of new technologies in educational practice. Despite the notion that students' familiarity with technological tools is essential for their learning development, the main question is still the following: does the utilization of technology affects the learning process ?The impact of using new technologies and tools on students’ learning achievements can be determined based on students’ progress in individual cognitive subjects, on students’ commitment, as well as on the attitudes, perceptions and readiness of teachers towards the utilization of technology. This paper explores whether and to what extent new technologies contribute to the strengthening of general education, special education and intercultural education (Roma students) students’ knowledge and skills. It appears that new technologies in classrooms seem to support educational practices. Teachers realize that their students use ICT as sources of reference, investigation and communication, w...
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Electric grid power consumption load is one of the fundamental areas that need to be faced to provide a sustainable and green ecosystem in smart cities. Consumption load as well as supply and availability of electricity to suppliers and... more
Electric grid power consumption load is one of the fundamental areas that need to be faced to provide a sustainable and green ecosystem in smart cities. Consumption load as well as supply and availability of electricity to suppliers and customers is a major issue to be faced to have a balanced smart city power grid infrastructure. Balancing in this case is assumed as a well-designed supply chain management system to be applied in the Smart City (SC) of Athens, Greece. Core of such a system is the knowledge of electric power consumption load per weekly basis of a year, that is the granularity of the proposed system is one week of the system’s operation. In this paper, focus is given on the electric load forecast component of an Energy Management System (EMS) such as the Independent Power Transmission Operator (ITPO) of Greece. Concretely, stochastic data of electric energy consumption load are used to predict the demand or offering of electric power in the future. This is achieved by...
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An Unmanned Aerial Vehicle (UAV) supply chain architecture is used to handle flood water leak incidents occurred by physical disasters in Smart Cities (SCs). Floods produce serious problems and inefficiencies in problematic sectors of... more
An Unmanned Aerial Vehicle (UAV) supply chain architecture is used to handle flood water leak incidents occurred by physical disasters in Smart Cities (SCs). Floods produce serious problems and inefficiencies in problematic sectors of water grid. Such incidents are treated as a supply chain problem, where each incident is assigned to a certain priority. On a trigger occurrence the nearest UAV reaches a certain flood water leak incident where the assigned plumber at the SC control system assesses the problem. SC personnel evaluate if it is a high significance incident to fix the problem in real time. In this paper, there are presented certain use cases, which are evaluated with proposed metrics incorporated by control system supply chain architecture to infer the optimum use case for SC recovery. Such a use case is proposed to be adopted by SC control system architecture to handle upcoming scenarios of flood physical disasters.
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The rising issue of corruption in the public sector could be solved by adopting an innovative technology such as blockchain, which offers data transparency and immutability. We present the opportunities of using blockchain technology in... more
The rising issue of corruption in the public sector could be solved by adopting an innovative technology such as blockchain, which offers data transparency and immutability. We present the opportunities of using blockchain technology in the transactions of the public sector of education and a conceptual approach for the adoption of this technology by the staff of the University of West Attica. Our research has practical value for the IT managers of the public sector who wish to integrate blockchain into public organizations because we also suggest gaming features for the main public sectors.
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The lack of digital literacy in the student community is high and depends on the academic background of the student. Although the skills gap can be filled by hiring additional academic staff and improving learning methods, it is obvious... more
The lack of digital literacy in the student community is high and depends on the academic background of the student. Although the skills gap can be filled by hiring additional academic staff and improving learning methods, it is obvious that funds or teaching time are not enough to cope with these changes. Our academic effort proposes a blockchain platform maintained by the students, which allows the students to exchange teaching duties and teach each other digital skills. The students adopt the role of the lecturer or the learner and receive reputation points as a reward. The platform is designed by using a gamified type of blockchain technology because it empowers a trustful and entertaining method for the exchange of teaching duties between the students.
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In this paper, the parameters that shape online reputation of a company and the two-way relation between the effect reputation has on consumer behavior and the effect consumer behavior has on reputation are examined. The contribution of... more
In this paper, the parameters that shape online reputation of a company and the two-way relation between the effect reputation has on consumer behavior and the effect consumer behavior has on reputation are examined. The contribution of this work lies in the fact that it concerns Greek consumers. Moreover, it is important to highlight the particularities of Greek consumers and to confirm or disprove international trends in their case. At the same time, issues related to the extraction and classification of elements related to reputation are highlighted. The answers given through this research and the questions that arise contribute to the formulation of effective strategies for the management of online reputation by the companies, even in cases of attacks and threats.
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One of the objectives of Assistive Technologies is to help people with disabilities communicate with others and provide means of access to information. As an aid to Deaf people, we present in this work a novel prototype Rule-Based Machine... more
One of the objectives of Assistive Technologies is to help people with disabilities communicate with others and provide means of access to information. As an aid to Deaf people, we present in this work a novel prototype Rule-Based Machine Translation (RBMT) system for the creation of large quality written Greek text to Greek Sign Language (GSL) glossed corpora. In particular, the proposed RBMT system supports the professional translator of GSL to produce high quality parallel Greek text GSL glossed corpus, which is then used as training data by the Statistical Machine Translation (SMT) MOSES [1] application system. It should be noted that the whole process is robust and flexible, since it does not demand deep grammar knowledge of GSL. With this work we manage to overcome the two biggest obstacles in Natural Processing Language (NLP) of GSL. Firstly, the lack of written system and secondly the lack of grammar and finally we have been able to lay the foundations for an autonomous tran...
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ABSTRACT This article discusses the concept of blockchain and its application to public administration research as a tool to increase trust in the government. The contribution of this article is that it unveils the advantages and... more
ABSTRACT This article discusses the concept of blockchain and its application to public administration research as a tool to increase trust in the government. The contribution of this article is that it unveils the advantages and disadvantages of blockchain so that both decision-makers (who intend to adopt this innovative technology to increase the transparency of the transactions in the public sector) and users (citizens and public servants) are well informed and prepared.
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ABSTRACT In this paper a novel approach for automatically annotating image databases is proposed. Despite most current schemes that are just based on spatial content analysis, the proposed method properly combines several innovative... more
ABSTRACT In this paper a novel approach for automatically annotating image databases is proposed. Despite most current schemes that are just based on spatial content analysis, the proposed method properly combines several innovative modules for semantically annotating images. In particular it includes: (a) a GWAP-oriented interface for optimized collection of implicit crowdsourcing data, (b) a new unsupervised visual concept modeling algorithm for content description and (c) a hierarchical visual content display method for easy data navigation, based on graph partitioning. The proposed scheme can be easily adopted by any multimedia search engine, providing an intelligent way to even annotate completely non-annotated content or correct wrongly annotated images. The proposed approach currently provides very interesting results in limited-size both standard and generic datasets and it is expected to add significant value especially to billions of non-annotated images existing in the Web. Furthermore expert annotators can gain important knowledge relevant to user new trends, language idioms and styles of searching.
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Intelligent Transportation Systems (ITSs) and their applications are attracting significant attention in research and industry. ITSs make use of various sensing and communication technologies to assist transportation authorities and... more
Intelligent Transportation Systems (ITSs) and their applications are attracting significant attention in research and industry. ITSs make use of various sensing and communication technologies to assist transportation authorities and vehicle drivers in making informative decisions and provide leisure and safe driving experience. Data collection and dispersion are of utmost importance for the proper operation of ITSs applications. Numerous standards, architectures and communication protocols have been anticipated for ITSs applications. In recent years, crowdsourcing methods have shown to provide important benefits to ITSs, where ubiquitous citizens, acting as mobile human sensors, help respond to signals and providing real-time information. In this paper, the problem of mitigating crowdsourced data bias and malicious activity is addressed, when no auxiliary information is available at the individual level, as a prerequisite for achieving better quality data output. To achieve this goa...
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Η συσκευασία υπάρχει ως μέσο προστασία του περιεχομένου εδώ και πάρα πολλά χρόνια, ωστόσο τα τελευταία και με την εξέλιξη της τεχνολογίας γίνεται η προσπάθεια να γίνει πιο «έξυπνη». Το ευφυές κομμάτι λοιπόν αρχίζει και εντάσσεται σε... more
Η συσκευασία υπάρχει ως μέσο προστασία του περιεχομένου εδώ και πάρα πολλά χρόνια, ωστόσο τα τελευταία και με την εξέλιξη της τεχνολογίας γίνεται η προσπάθεια να γίνει πιο «έξυπνη». Το ευφυές κομμάτι λοιπόν αρχίζει και εντάσσεται σε ολοένα και περισσότερες συσκευασίες με σκοπό την πληρέστερη ενημέρωση του καταναλωτή για το προϊόν, αλλά και τη προσπάθεια να δεθεί ο καταναλωτής με το προϊόν μέσω της διαδραστικότητας που προσφέρει η ευφυής συσκευασία. Ενώ η ευφυής συσκευασία θέλει να απευθυνθεί σε ένα μεγάλο φάσμα του καταναλωτικού κοινού, η χρήση τελευταίων τεχνολογιών τη περιορίζει σε ένα κομμάτι του κοινού που τις γνωρίζει και μπορεί να τις χειριστεί καλύτερα. Το βασικό πρόβλημα λοιπόν, είναι ότι η έννοια και η χρησιμότητα της ευφυούς συσκευασίας είναι άγνωστες για τους περισσότερους καταναλωτές, αλλά, όταν τους γίνει μία αναλυτική περιγραφή των δυνατοτήτων τους εμφανίζονται θετικοί στο να τις χρησιμοποιήσουν. Για να ξεπεραστεί αυτό το πρόβλημα θα πρέπει να υπάρξει μία πιο λεπτομερή...
Many automatic image annotation methods are based on the learning by example paradigm. Image tagging, through manual image inspection, is the first step towards this end. However, manual image annotation, even for creating the training... more
Many automatic image annotation methods are based on the learning by example paradigm. Image tagging, through manual image inspection, is the first step towards this end. However, manual image annotation, even for creating the training sets, is time-consuming, complicated and contains human subjectivity errors. Thus, alternative ways for automatically creating training examples, i.e., pairs of images and tags, are crucial. As we showed in one of our previous studies, tags accompanying photos in social media and especially the Instagram hashtags can be used for image annotation. However, it turned out that only a 20% of the Instagram hashtags are actually relevant to the content of the image they accompany. Identifying those hashtags through crowdsourcing is a plausible solution. In this work, we investigate the effectiveness of the HITS algorithm for identifying the right tags in a crowdsourced image tagging scenario. For this purpose, we create a bipartite graph in which the first type of nodes corresponds to the annotators and the second type to the tags they select, among the hashtags, to annotate a particular Instagram image. From the results, we conclude that the authority value of the HITS algorithm provides an accurate estimation of the appropriateness of each Instagram hashtag to be used as a tag for the image it accompanies while the hub value can be used to filter out the dishonest annotators.
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Every year, millions of letters/parcels containing illicit goods are detected by customs authorities, which use traditional security screening equipment. However this equipment cannot detect all kinds of illicit goods and the detection... more
Every year, millions of letters/parcels containing illicit goods are detected by customs authorities, which use traditional security screening equipment. However this equipment cannot detect all kinds of illicit goods and the detection procedure heavily depends on the attention of the customs officer. In order to achieve sufficiently fast intelligent screening of the large volumes of letters/parcels and detect all common kinds of threats, this paper proposes a highly innovative architecture well-beyond the state-of–art. In particular the proposed architecture monitors every letter/parcel by incorporating: (a) terahertz/X-ray sensors, (b) chemical, biological, radiological and nuclear (CBNR) sensors, (c) artificial robot-noses for narcotics, explosives etc., (d) magnetometers for weapons, firearms, banknotes etc., (e) acoustic sensors for liquids/gases/solids, (f) weight/pressure sensors to measure weight distribution, size and shape. Sensory information can be: (a) used to create a ...
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The current paper is a part of a master dissertation carried out at the Open University of Cyprus. Starting from an individual to a multinational corporation level we are looking to find, understand and define the purpose, the need and... more
The current paper is a part of a master dissertation carried out at the Open University of Cyprus. Starting from an individual to a multinational corporation level we are looking to find, understand and define the purpose, the need and the impact of managing the impressions made. We argue that strategies may vary regarding the type of business. We suggest that anybody has an opinion as soon as they identify the brand. This opinion is disseminated and collectively can be seen as reputation. The progress in communication is implying bigger social influence between the people, trends are changing fast. We are presenting different tools to find these insights, which perform Online Reputation Management (ORM), free, paid or open source. Using theory from social science and technological facts, we discuss possible caveats. Finally we aim to use python scripts in order to collect, preprocess and analyze real data to see it in practice through the prism of a real business entity.
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The entrance of Social Media in everyday life has changed the way people communicate with each other. This has affected all areas and the daily routine of people. This dynamic entrance of Social Media also affects the field of health, one... more
The entrance of Social Media in everyday life has changed the way people communicate with each other. This has affected all areas and the daily routine of people. This dynamic entrance of Social Media also affects the field of health, one of the most important areas of people's lives. Doctors and Dentists throughout Greece are approximately 78,760 according to the Hellenic Statistical Authority data for 2017. The competition in this field is very high and medical marketing has become an indispensable tool for all health professionals. This study focuses on the Doctor-patient relationship in the era of the continuously use of Social Media. This Paper highlights matters arising both ways, from the patient's side but also from the perspective of a Doctor. Key-Words: Social media, Social stereotypes, Doctors, Patients, Medical marketing, Social Computing
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During the last decade, the problem of inequality in education has been studied by several researchers, especially regarding urban and rural (inaccessible) areas. Most studies conclude that funding and adoption of new technologies are... more
During the last decade, the problem of inequality in education has been studied by several researchers, especially regarding urban and rural (inaccessible) areas. Most studies conclude that funding and adoption of new technologies are necessary to reduce inequalities. However they do not propose any specific means to overcome these inequalities. Towards this direction, in this paper a specific method is proposed that contributes to the reduction of inequalities, without demanding any funding. The method is designed especially for inaccessible areas (including isolated islands), which face network connectivity issues or Internet speed becomes very slow. In particular knowledge-based video summarization is introduced, to overcome boredom, frustration, anger etc. when students try to watch online educational videos, using limited throughput channels. The main question is: which information is less important so that it can be excluded or roughly described ? In this paper students play t...
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This paper proposes an innovative relevance feedback algorithm for wall-content selection in social media. The procedure results in an iterative loop, which recursively updates a weighted distance. The distance is then used for finding... more
This paper proposes an innovative relevance feedback algorithm for wall-content selection in social media. The procedure results in an iterative loop, which recursively updates a weighted distance. The distance is then used for finding multimedia items that are relevant to a user's preferences. To do so, the activity log of the user under investigation is considered and his/her attention at previous intervals is analyzed. Another novel point of the proposed approach is the incorporation of friends' attention into the relevance feedback scheme. In particular, interactions among users and posted multimedia items are considered as an explicit crowdsourcing activity. By this way some multimedia items receive more attention, while some others receive less or no attention. By analyzing these social interactions, a social computing framework is formed, which affects the evolution of the content selection process. Overall, the iterative relevance feedback algorithm takes into consideration visual features, activity log and social attention, in order to select the wall information of each social media user. Experimental results and comparisons on real data, exhibit the advantages of the proposed scheme and future directions are also discussed.
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In this paper, multiresolution organization of social media users’ profiles is proposed that enables fast browsing and effective transmission of characteristic profiles. The scheme results in the construction of a novel three-layer tree... more
In this paper, multiresolution organization of social media users’ profiles is proposed that enables fast browsing and effective transmission of characteristic profiles. The scheme results in the construction of a novel three-layer tree structure. At layer 0 the root-node contains the most representative profile among class representatives (CRs). Each node of layer 1 represents a class of profiles, while in layer 2 the full resolution is available (all profiles). The nodes of the proposed tree structure contain viewing elements and in this paper we focus on the extraction of viewing elements for layers 0, and 1. Towards this direction the viewing elements of layer 1 are optimally extracted using an interpolation method, while the viewing element of layer 0 is estimated from the viewing elements of layer 1. The resulting tree-structure enables users to quickly browse and detect profiles of interest, by selecting the viewing elements they like. Experimental results on reallife social media users indicate the promising performance of this innovative scheme.
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Spam is an enemy of our resources and mood. In this paper spam detection is examined in case of social media content. In particular a typical Bayesian classifier is setup and trained on real data. Additionally a social computing method is... more
Spam is an enemy of our resources and mood. In this paper spam detection is examined in case of social media content. In particular a typical Bayesian classifier is setup and trained on real data. Additionally a social computing method is also introduced, which analyses the attention that content receives. Finally a novel hybrid approach is implemented, where content is characterized as spam when both the Bayesian classifier and the social attention model agree on content’s evaluation. Experimental results on real world Twitter content, exhibit the promising performance of the proposed scheme.
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During the last decade Twitter has undergone a massive growth and several algorithms have been proposed for analysing its content. A common challenge is identifying user interests. In this work, we focus on personalizing the consumption... more
During the last decade Twitter has undergone a massive growth and several algorithms have been proposed for analysing its content. A common challenge is identifying user interests. In this work, we focus on personalizing the consumption of tweets by taking into consideration the tweets profile of each user (average tweet). In particular for each user an average vector is estimated that maps her/his interests. Then the distance between tweets that are posted on a user’s wall is estimated. In this process the average tweet is also considered. Finally a graph of tweets is constructed and the minimum distance path is estimated. Experimental results on real life data exhibit the advantages and limitations of the proposed scheme.
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Physical disasters can highly impact the well-being of people living in Smart Cities (SCs). Many citizens, including children and seniors, can face serious issues and survival risks after a physical disaster. Internet of Things (IoT)... more
Physical disasters can highly impact the well-being of people living in Smart Cities (SCs). Many citizens, including children and seniors, can face serious issues and survival risks after a physical disaster. Internet of Things (IoT) technology can be used to mitigate such risks by providing the technological solution to assist citizens in extreme situations. Such extreme physical disasters are earthquakes. In earthquakes houses and public buildings may collapse and capture many individuals in the ruins. Lives of citizens are seriously threatened. After an earthquake, in a hostile environment, ambulances should take control and provide solutions to fundamental human needs. In this paper an Emergency Medical Service (EMS) system is proposed, enabled with IoT technology. Our system incorporates, sensors and IoT equipment embedded to ambulances to assist and give solutions to peoples' problems after an earthquake. Specifically two use cases are examined and a dynamic routing algorithm is proposed to face the problem. The overall scheme is evaluated using synthetic data from the SC of Manchester, United Kingdom. Certain metrics are introduced to compare the proposed use cases in the context of the emerging SCs technological environments.
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Smartphone sensing enables efficient Time-of-Arrival (ToA) estimation of moving cyclists towards traffic lights in a Smart City. GPS sensors locate the actual position of cyclists on their way to traffic lights. Since the constant use of... more
Smartphone sensing enables efficient Time-of-Arrival (ToA) estimation of moving cyclists towards traffic lights in a Smart City. GPS sensors locate the actual position of cyclists on their way to traffic lights. Since the constant use of GPS sensors drain the battery of the smartphones there is a need of efficient energy consumption techniques. In this paper we propose a velocity based ToA estimation system to face the GPS energy consumption inefficiency. In addition we aim to enable efficient cycling in Smart Cities by turning traffic lights to green proactively thus achieving overall citizen's wellbeing.
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Crowdsourcing has been extensively used in the private sector and recently adopted by the public sector. The current paper discusses the use of the mobile crowdsourcing in the public administration from both managerial and technological... more
Crowdsourcing has been extensively used in the private sector and recently adopted by the public sector. The current paper discusses the use of the mobile crowdsourcing in the public administration from both managerial and technological perspectives by exploring its current use and research challenges. The authors classify the mobile crowdsourcing in four categories, based on the application areas: Infrastructure maintenance, environmental reporting, critical situation reporting, and crime watch reporting. Each application area is examined for its research challenges and contribution in the crowdsourcing research area.
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In this paper a multi-source video summarization scheme is proposed, which is focuses on novel concepts of the Internet of Things. The proposed scheme assumes several different cameras asynchronously recording the same event from... more
In this paper a multi-source video summarization scheme is proposed, which is focuses on novel concepts of the Internet of Things. The proposed scheme assumes several different cameras asynchronously recording the same event from different angles, positions, heights etc. One of its main novelties is in the area of content evaluation. More specifically a social computing approach is proposed in order to find out which of the recordings attracts more attention. Attention is estimated by considering a social network environment where each user that records the event can post his/her material and let his/her friends to interact with it. Simulation results are presented, to denote the full potential of the proposed scheme, its advantages as well as important issues for future work. Key-Words: Internet of Things, Social Computing, Video Summarization, Multiple Sources